Color Change of One Element in a Mermaid Sequence Diagram?

Question

I'm using Mermaid to create a sequence diagram in Markdown. I'd like to highlight some of the participants and to gray some of the arrows.

How can that be done?

Answer 1

Nowadays, it isn't possible to style sequence diagrams. There is an open issue in their bugtracker. Click the link and vote for it :-)

You can style other types of diagrams, as answered by @lutz-dieckhofer.